Absorption and adsorption refrigerating apparatus



Wlrch 3, 1942. N. ERLAND AF KL EEN 2,274,680 I ABSORPTION AND ABSORPTION REFRIGERATING APPARATUS Filed July 16, 1957 3 Sheets-Sheet l M manila fiild Erhna zfjileen March 3, 1942. ERLAND AF KLEEN 2,274,680

ABSORPTION AND ADSORPTIQ N REFRIGERATING APPARATUS Filed July 16, 1937 3 SheetS-rSheetQ March 3, 1942. N. ERLAND AF KLEEN ABSORPTION AND ABSORPTION REFRIGERATING APPARATUS Filed July 16, 1957 3 Sheets-Sheet 3 rb nib .Erhrql like -Patented Mar. 3, 1942 UNITED STATES PAT F 1 ABSORPTION AND ABSORPTION I BEFRIGERATING APPARATUS Nils Erland af Kleen, Oxford, England Application July 16, 1937, Serial No. 154,090

' In Great Britain July 23, 1936 9 Claims.

This invention relates to absorption or adsorp-- tion refrigerating apparatus of the kind in which the boiler absorber or adsorber contains dry salts or other materials capable of absorbing or adsorbing the refrigerant when in gaseous form and of giving up such refrigerant during the boiler absorber, or adsorber, generation period. For convenience of reference, the term absorption hereinafter mentioned, and likewise absorber," will be used to include adsorption," and of course, in like manner adsorber. Similarly the expression dry salts" will be used hereinafter to mean dry salts or other materials capable of absorbing or adsorbing gaseous refrigerant.

In refrigerators of the type mentioned, a serious drawback has been encountered arising from hitherto unpreventable feed-back to the boilerabsorber of quantities ,of refrigerant in liquid condition. The dry salts used for absorption deteriorate very rapidly when a liquid falls upon them, so that such liquid feed-back seriously impairs the action of the boiler absorber.

In existing refrigerators feed-back of liquid refrigerant to the boiler absorber is mainly due to one or both of the following causes. The first and more usual cause of liquid feed-back is due to the fact that when the boiler absorber is generating, and a gaseous refrigerant is driven off, certain amounts of gaseous refrigerant become condensed in the outlet pipe from the boiler absorber. Such condensed refrigerant returns in liquid form into the boiler absorber and acts upon the dry salts therein. This condition is to be found when the boiler-absorber is arranged at the same level as, or below the level of, the condenser (or collecting tank and evaporator). The second cause of back feed of liquid arises when the refrigerator is transported or moved, there being a tendency for liquid refrigerant present in the evaporator to flow back intothe boiler-absorber and this condition is to be found when the boiler-absorber is arranged at thesame level prevented, or, alternatively, will be directed into, and trapped within a compartment of the boiler absorber and thereafter evaporatedduring the generation period of the absorber.

With the above and other objects in view which will appear as the de ription proceeds, the invention resides in the novel features hereinafter more clearly set forth in the following description, illustrated by way of examples in the accompanying drawings and more particularly pointed out in the appended claims.

Referring to the drawings in which numerals of like character designate similar parts throughout the several views, I

Fig. 1 is a diagrammatic view of an intermittently operating absorption refrigerator showing,

one form of liquid collecting means arranged within the boiler absorber.

Fig. 2 is a view similar to Fig. 1 but showing a different arrangement of liquid collecting means in the boiler absorber.

Fig. 31s a similar view of a modified form of v, liquid collecting means shown in Fig. 2.

as, or above or below the level of the condenser (or collecting tank and evaporator).

It is a primary object of the present invention to provide means for overcoming the difficulty of back flow of liquid into the boiler absorber in a.

refrigerator of the absorption type, whether such flow be from condensed refrigerant or actual liquid refrigerant.

According to the invention, therefore, there is provided in refrigerators of the type mentioned, means associated with the outlet pipe from the boiler absorber such that any liquid feed-back through such outlet pipe will be either positively Fig. 4 is a diagrammatic view of a modified form of intermittently operating absorption apparatus and illustrating liquid collecting means arranged outside the boiler absorber, and

Fig. 5 is a view similar to Fig. 3 but showing a still further modification of liquid collecting means arranged in the boiler absorber.

In the drawings, referring first to Fig. 1, the 4 reference character ll represents generally a boiler absorber in the form of a cylindrical shell 82 having a central heating flue I3 in which is arranged a suitable heating element such for example as a gas burner It. The shell l2 en-' closes a plurality of annular trays l5, which contain or support dry salts I6 capable of absorbing a gaseous refrigerant and of giving up such refrigerant under heat. The gaseous refrigerant driven out of the boiler absorber passes by way of outlet pipe 20 to a condenser H where it con-- denses and flows to the evaporating system shown I minate within a short distance from the bottom of the boiler absorber. The lowest tray of the boiler absorber is arranged so as to be spaced a short distance from the bottom to form an annular compartment 23. It is in this annular compartment that the conveyor pipe 2| terminates.

It will be appreciated that during the generation period of the boiler-absorber just described,

gaseous refrigerant driven off will pass out through the outlet pipe 20, and any liquid condensed in the same will run back and directly enter the conveyor pipe 2| described. Such liquid will then run down the conveyor pipe and be effectively trapped in the annular compartment 23. The liquid collecting in the annular compartment will be evaporated in due course and will pass in gaseous form up through, or around the pipe 2|, or through the trays i5 of the boiler.

absorber, by means of the usualapertures arranged in said trays, and will escape once more through the outlet from the boiler absorber to pass to the condenser l'l, collecting tank i8 and evaporator coils i9. When the supply of heat is cut oil, the liquid refrigerant will evaporate in the coils 9 for the production of cold, and return to the boiler absorber to be re-absorbed by the dry salts.

As shown in Figures 2 and 3, the outlet pipe 20 from the boiler absorber may depend into a tray 3|, disposed above the top-most tray i5 and arranged on one side of the heating flue i3 (Figure 2) or a similarly disposed tray 32 (Figure 3) surrounding said flue, in either case returningliquid refrigerant is trapped in said tray to prevent deterioration. of the absorbent, and may be driven off from the tray during the next generation period.

While in the above described forms of the invention, the liquid refrigerant is trapped in trays or compartments located. inside the boiler absorber, the invention also contemplates the trapping of liquid refrigerant in chambers or vessels outside the boiler absorber as illustrated in Fig. 4. Moreover as shown therein, the invention is also applicable to an intermittently operating absorption refrigerator in which a plurality of boiler absorbers containing dry salts are arranged in batteries designated as and 43. In this case an outlet 34 from the uppermost batteiy 35 would be connected to a chamber 36 of spherical form. The connection would be at the side of the chamber, and the outlet pipe 20 leading to the evaporator would be brought in at the top of the chamber 36, whilea conveyor pipe 38 for the removal of condensed liquid would be brought into the chamber 36 at the lower side thereof. As in the previous constructions, the end of the conveyor pipe 38 within the chamber 36 would be of funnel-like form 40, and the outlet pipe 20 leading to, the evaporator would depend into this funnel-like mouth. The lower end of the conveyor pipe 38 would terminate in a second spherical chamber 4|, and at a point with in said chamber above the termination of the conveyor pipe, a further pipe 42 would be arranged and connected with the lower-most battery 43 of the boiler absorber. Said further pipe 42 would preferably have the form of a U-tube 44, one leg of the tube being substantially within the spherical chamber 4|, and the open end of such leg being arranged above the level of the termination of the conveyor pipe 38.

The boiler absorbers 35 and 43 are shown heated by a circulating fluid system formed by a boiler 82, a flow pipe 92 leading to a central heating chamber 86 in the boiler absorber 35, a connection 30 leading to a central heating chamber 84 in the boiler absorber 43, and a return pipe 88 leading back to the boiler 82. A gas burner i4, or other suitable heating element is provided scribed, any liquid formed by condensation ofgaseous refrigerant in the outlet 20, will be conveyed through the conveyor pipe 38 into the lower spherical chamber 4|, in which chamber evaporation may take place and any evaporated gases passing through the .U-tube connection 44 back to the boiler-absorber. If the unit is turned upside down, the U-bend 44 will prevent any flow of liquid refrigerant back to the boiler-absorber. The lower chamber 4| might be dispensed with in certain cases and the liquid then trapped in the upper spherical chamber.

An alternative construction within the scope of the invention consists in providing a boiler chamber of the super-posed tray type, with a top tray carrying materials capable of selective absorption (see Figure 5). Such materials would absorb or adsorb any liquid entering the boiler but would not absorb gases. The outlet pipe 20,

woulddepend over the top tray 46 carrying the requisite absorbent and therefore any undesirable feed-back of liquid would be effectively trapped and the liquid absorbed in said top tray. From the foregoing it is believed that the con struction and advantages of the invention may be readily understood by those skilled in the art without further description, it being understood that numerous changes may be made in the details disclosed without departing from the spirit of the invention as set out in the following claims:

'I claim:

'1. In absorption refrigerating apparatus of the type operating intermittently in the expulsion and absorption phases, respectively, and including at least one closed system for a refrigerating agent, said system consisting of at least one generator-absorber having a shell enclosing a body of solid absorbent material, a plurality of elements arranged to provide a condenser. and an evaporator coupled'in series, means connecting said generator-absorber to said condenser tonermit therefrigerating agent to be withdrawn from said plurality of elements during the absorption phase operation of said apparatus and to be expelled from said generator-absorber to said elements during the expulsion phase operation of said apparatus, and means for intermittently heating said generator-absorber for the expulsion phase operation of said apparatus: the combination with said body of solid absorbent material within the shell adapted to absorb said refrigerating agent received by the shell from said connecting means, of means additional to the generator-absorber shell cooperating with the aforesaid connecting means to segregate liquid refrigerant from refrigerant vapor and to form such liquid refrigerantin a body out of contact with said expanded solid absorbent material in said shell, and to enable the refrigerant vapor free from any liquid refrigerant to be absorbed by the said absorbent material.

2. In absorption refrigerating apparatus of the type operating intermittently in the expulsion and absorption phases. respectively, and including at least one closed system for a refrigerating agent, said system consisting of at least one gen- 4 erator-absorber having a shell enclosing a body of solid absorbent material, a plurality of elements arranged to provide a condenser, and an evaporator coupled in series, means connecting said generator-absorber to said condenser to permit the refrigerating agent to .be withdrawn from said plurality of elements during the absorption phase operation of said apparatus and to be expelled from said generator-absorber to said elements during the expulsion phase operation of said apparatus, and means for intermittently heating said generator-absorber for the expulsion phase operation of said apparatus; the combination with said body of solid absorbent material within the shell adapted to absorb refrigerant vapor received by the shell from said connecting means, of a reservoir-like trap interposed in the path of the refrigerating agent conducted to the shell by said connecting means,-as the refrigerating agent moves towards the absorbent material to be absorbed thereby, said trap having an opening to allow the free movement therefrom of the vapor of said refrigerating agent, said trap having walls to isolate liquid entrained by said refrigerating agent in a body separate from the vapor and said walls being impervious to hold the liquid out of contact from said absorbent material.

3. In an absorption refrigerating apparatus of the intermittent type, the combination with a generator-absorber having solid absorbent therein and means for heating said solid absorbent; of a plurality of elements arranged to provide a condenser, and an evaporator coupled in series, means connecting said generator-absorber to said condenser, and means cooperating with said connecting means to segregate refrigerant vapor from any liquid entrained therein and to form such liquid in a body out of contact withthe solid absorbent.

4. The combination with absorption refrigerating apparatus of the type operating intermittently in the expulsion and absorption phases, respectively, including at least one closed system for a refrigerating agent, said system consisting of at least one generator-absorber containing solid absorbent material, a condenser, and an evaporator, all coupled in series, and means for heating said generator-absorber, for the expulsion phase operation of said apparatus; of a liquid collecting trap interposed in said system between said absorbent material in said generatore absorber and said condenser, to segregate refrigerant vapor from any liquid entrained therein and to form such liquid refrigerant in a body out of contact with said absorbent material.

5. In absorption refrigerating apparatus of the type operating intermittently in the expulsion and absorption phases, respectively, including at least one closed system for a; refrigerating agent, said system comprising at least one generatorabsorber containing" solid absorbent material, a plurality of elements arranged to provide a condenser, and an evaporator coupled in series, and means connecting said generator-absorber to said condenser to permit the refrigerating agent to.

be withdrawn from said plurality of elements and absorbed by said absorbent material during the absorption phase operation of said apparatus and to be expelled from said generator-absorber to said elements during the expulsion phase operation of said apparatus, and means for heating said generator-absorber for said expulsion phase operation; means for preventing said refrigerating agent in liquid form from contacting said absorbent material, comprising a compartment in said generator-absorber cooperating with said connecting means for separating liquid fromvapors and to for-msuch liquid in a body, said compartment being isolated'from said absorbent ma terial and having an opening to permit free movement therefrom of vapors. V

6. In absorptionrefrigerating apparatus of the type operating intermittently in the expulsion and'absorption phases, respectively; including at least one closed system for a refrigerating agent,

said system comprising at least one generatorabsorber containing solid absorbent material, a plurality of elements arranged to provide a condenser, and an evaporator coupled in series, and means connecting said generator-absorber to said condenser to permit the refrigerating agent to be withdrawn from said plurality of elements and absorbed by said absorbent material during the absorption phase operation of said apparatus and to be expelled from said generator-absorber to said elements during the expulsion phase operation of said apparatus, and means for heating said generator-absorber for said expulsion phase operation; means for. preventing said re-. frigerating agent in liquid form from contacting said absorbent material, comprising a tray in said generator-absorber cooperating with said connecting means for separating liquid from vapors and forming such liquid in a body, said tray being isolated from said absorbent material and having an opening to permit free movement therefrom of vapors.

, .7. In absorption refrigerating apparatus of the said element's during the expulsion phase operation of said apparatus, and means for heating said generatorabsorber for said expulsion phase operation; means for preventing said refrigerating agent in liquid form from contacting said absorbent material, comprising a down-pipe in communication at one end with the upper portion of said generator-absorber, and at its other end with the lower portion of said generatorabsorber, and trap means isolated from the absorbent material and cooperating with said.

down-pipe for separating liquid from vapors and forming such liquid in a body out of contact with said absorbent material.

8. In absorption refrigerating apparatus of the intermittent type embodying a closed system formed by a plurality of elements including gen-.

crater-absorber containing solid absorbent material, condenser and evaporator, and an outlet conduit from said generator-absorber to permit the passage of the generated refrigerant to the condenser and evaporator during the generating periods, and the return of the evaporated material from the evaporator to the generator-absorber during the'absorbing periods, said outlet conduit-extending'vertically from the top of the generator-absorber; means for preventing the refrigerant in liquid form from contacting the solid absorbent in saidgenerator-absorber, comprising a chamber adjacent the bottom of said gener-'- ator-absorber, a down-pipe in said generatorabsorber terminating atits lower end in communication with said chamber, and a funnel mouth at the upper end of said down-pipe arranged below the lower end of said outlet conduit to receive any refrigerant liquid gravitating from said outlet pipe and convey the same to said chamber.

9. ,In a refrigerating apparatus of the intermittent absorption type embodying a closed circuit formed by a plurality of elements including generator-absorber, condenser, and evaporator,

during the generating periods; the combination with said circuit of means for receiving and holding outcf contact with'said solid absorbent material any refrigerant in liquid form in said cirl0 cuit.

- NILS E. A! KLEEN. 

